Production and treatment of artificial materials



Patented Sept. 1, 1936 U i H STATES raonucrroN AND TREATMENT or ARTIFICIAL MATERIALS Henry Dreyfus, London, England No Drawing.

Application February 11, 1933,

Serial No. 656,361. In Great Britain March 10 Claims.

This invention relates to improvements in the production and treatment of artificial materials such as filaments, yarns, ribbons and the like, and fabrics and other products obtained there- 5 from, and particularly to processes for the incorporation of insoluble compounds therein.

Processes for the incorporation of finely divided insoluble compounds in artificial materials have been described in U. S. Patents Nos. 1,806,048,

[ 1,821,464 and 1,817,741, according to which materials are treated with a solution of a suitable salt, for example, tin chloride, and then with a fixing agent. Again, the dyeing and printing of materials containing such insoluble substances is described in U. S. Patents Nos. 1,806,043, 1,805,467

. and 1,805,468, while U. S. application S. No. 455,-

969 filed May 26, 1930 is concerned with a process of weighting or mordanting in which a metallic radicle ora precipitant is incorporated in the 0 spinning solution from which the artificial materials are formed, the production of the insoluble compound being achieved by treating the materials after their formation with a solution containing a precipitant or a metallic radicle respec- 35 tively. Further, U. S. applications S. Nos. 444,- 622 filed April 15, 1930 and 481,806 filed September 13, 1930 describe processes in which the insoluble substance in a finely divided form is added directly to the spinning solution, in which case m no further treatment of the formed products is necessary.

I have now discovered that artificial materials containing finely divided insoluble substances may also be obtained by incorporating g suitableinsoluble compounds in the materials, and then treating them with reagents which will convert the compounds into the form in which they are required in the finished product. This method of procedure greatly extends the number of compounds which may be employed in order to introduce the desired metallic or acid radicle into the materials, since a large number of substances which, by reason of their solubility in water or other liquids, are unsuitable for weight- ,5 ing or other purposes for which finely divided substances are '-employed, are nevertheless insoluble in acetone and other media and may thus be incorporated from dispersions in these liquids and then be transformed into a final, preferably water-insoluble, form. While I prefer to carry out my invenion by incorporating the primary insoluble compound in the spinning solution and treating the products after their formation in order to produce the secondary compound, yet the process may also be performed by incorporating the primary insoluble compounds in the formed products, which are then treated in order to obtain the final substance required.

'According to the present invention therefore, 0 artificial materials such as filaments, yarns, ribbons and films, and fabrics and other products obtained therefrom, having improved properties, and particularly an increased resistance to heat, may be obtained by incorporating therein finely divided insoluble substances at any stage of their 5 production, and subsequently converting these substances into other insoluble compounds by treatment of the formed materials.

While the increase of the heat resistance of artificial materials forms an important part of the present invention, yet it is by no means limited thereto, and may also be applied to the weighting or delustring of materials, and to improving their afiinity for various classes of dyestufi's other than the insoluble colours customarily 1 applied from dispersions.

The finely divided compound employed is preferably inorganic, and while it is of course in any case insoluble in the spinning solution,, or in the medium by means of which it is applied to the 20 formed filaments or other products, it may or may not be soluble in the medium in which the reagent employed to convert it into its final form is applied.

The invention is of particular value in relation to the production or treatment of artificial materials from cellulose acetate, but it may also be applied to the formation or treatment of materials from other esters of cellulose, for example cellulose nitrate, cellulose formate, propionate and butyrate and other organic esters of cellulose, methyl, ethyl and benzyl cellulose or other cellulose ethers, mixed esters, such as cellulose nitro-acetate, and mixed ether-esters, e. g. ethyl cellulose acetate and oxyethyl cellulose acetate. Further, materials containing regenerated cellulose, such as are obtained for example by the viscose, cuprammonium and nitrocellulose processes, may also be produced or treated according to the process of the present invention.

Among suitable primary substances which may be used may be mentioned hydroxides of aluminium, zinc and tin, barium carbonate, mono- -and (ii-sodium phosphates, sodium silicate, sodium carbonate, sodium sulphate, sodium stannate, sodium zincate, barium chloride and magnesium and zinc sulphates. According to one method of carrying out the invention substances such as, for example, the hydroxides of aluminium, zinc and tin,'and barium carbonate, may 50 conveniently be converted into their final form by treatment with acids or acid salts, preferably in dilute solution. Thus, filaments containing hydroxides of tin or zinc may be passed through or otherwise treated with a solution of phosphoric acid or sodium dihydrogen phosphate to convert the hydroxides into insoluble phosphate. Alternatively the formed products may be treated with aqueous solutions of suitable substances, which by double decomposition or other reaction will .60

convert the compound present in the materials into its final form. Thus, for example, an acetone solution of cellulose acetate containing fine ly divided monoor di-sodium phosphate or so- 5 dium sulphate may be spun in the usual manner, and the formed products subsequently treated with a solution containing zinc sulphate or barium chloride respectively to precipitate zinc phosphate orbarium sulphate as the case may be.

. The treatment of the formed products may be carried out continuously with their production e. g. by dry or wet spinning methods, and when the latter methods are employed the reagent employed for the conversion of. the insoluble compound into its final form may, if desired, be present in the coagulating bath itself. Alternatively the process may comprise a separate operation from that of theproduction of the materials, and, for example, filaments or yarns may be passed from bobbins or other devices through baths containing the reagents.

The treatment of the formed filaments or other products, whether for the introduction of the primary insoluble compound or for its conversion into its final form, or both, may advantageously be carried out when the'materials are in a swollen condition, either by reaison of previous treatment with a swelling agent or on account oi? the presence of the swelling agent in the bath from which the insoluble compounds or subsequent reagents are applied. Suitable swelling agents which may be employed in connection with the treatment of artificial materials containing cellulose acetate or other organic derivatives of cellulose comprise aqueous solutions of alcohol, acetone, glycollic acid, phenol and thiocyanates and other organic and inorganic substances, as referred to, for example, in U. S. Pat- 40 The swelling agent may, it desired, form a large proportion or even the whole of the liquid medium from which the insoluble compound is applied, or by means of which it is converted into I the final form. Thus, for example, cellulose acetate filaments may be treated with an alcoholic dispersion of zinc sulphate, and subsequently passed through asolution of disodium phosphate, or alternatively materials containing finely divided sodium sulphate may be treated with an 60 aqueous solution of barium thiocyanate which, besides yielding the cation of the finalxinsoluble compound, also acts as a swelling agent. a Moreover, the combination oi. these two methods is not excluded.

56 Further methods of application 01' the insoluble compound or subsequent reagent include pad-. ding and spraying, while suitable substances e. a. metallic oxides, may if desired beap'plied by proiection, as from a Schoop pistol. By means of a 00 stencil it is thus possible to obtain pattern effects,

which is-particularly useful when the process of the present application is applied to delustring or increasing aflinity for dyes. Methods adapted to obtain the insoluble substance in a voluminous 66 condition by impregnating the .materials comprising organic derivatives of cellulose with a able mill, for example a .ball or colloid mill, either 76 alone or in. coniunction with other substances.

For example, they may be ground in the presence of a portion of the solvent employed for. the spinning solution or of a portion of the solution itself,

or again, the cellulose acetate or other derivative of cellulose forming the base of the spinning 6 solution may be present in the dry state. Alternatively, when incorporating the primary insoluble substance by'treatment of the formed products, grinding may be carried out in the presence of the liquid medium in which the substances 10 and then incorporated in the spinning solution or 20 solvent thereof, in which it is insoluble. It may thus be obtained in' a finely divided form.

The amount of finely divided material incorporated in the artificial products will of course depend upon the purpose for which it is present. 25 For example, when it is desired to weight the materials high proportions such as 20%, 30%, or even more may be employed, while in the case of its application with the object of increasing the heat resistance at the materials, for 30 which purposes, as is stated above, the invention has been found to be particularly valuable, lower proportions, for example of 10% or 5% have been found satisfactory.

When it is desired to increase the heat re- 35 sistance o! the artificialflmaterials it has been found that particularly good results may be obpresent invention, or as a separate operation.

The process '01 the present invention may be 50 carried out at normal'or elevated temperatures,- or even at low temperatures, though this is less desirable, and in the case when high temperatures are employed, substances which tend to diminish the delustring action of hot liquids, such v as, for example, are referred to in U. S. Patents Nos. 1,765,581 and 1,808,061, may beadded to g the treatment baths. l a 1. V Y The following examples illustrate the invention but are not to be considered as limiting it 0 Example 1 A 25% solution 01' cellulose acetate in acetone containing 2-3% of sodium sulphate in a finelydivided form is spun into an aqueous solution containing about 80 grams o'ibarium thiocyanate and grams of ammonium thiocyanate per a litre. On emerging Irom the coagulating bath Example 2 I A. 25% solution of cellulose acetate in acetone 15 containing 2-3% of freshly precipitated tin hydroxide is spun through suitable orifices into an evaporative medium. The yam thus obtained is immersed in hank form in a bath containing 20-30% of tri-sodium phosphate at a temperature of 50-60 C. Afterl5-30 minutes the yarn, which is partially saponified and contains tin phosphate, is removed, washed and dried.

Example 3 A cellulose acetate yarn in hank form is soaked for about 30-45 minutes, at 20-30 C. in a dispersion of sodium hydrogenphosphate in alcohol, obtained, for example, by stirring a saturated solution of the salt into alcohol. The yarn is then lifted andjmrnersed without washing in a cold solution of [sodium zincate containing about 30-35 grams NaOH and -20 grams ZI 1(OH)2 per litre. After about A hour the goods are restantially insoluble in water and in the medium in which the reagent employed to convert the first substance into the final substance is applied.

What I claim and desire to secure by Letters Patent is:-

1. Process for the manufacture of artificial filaments, threads, yarns, films; fabrics and like materials containing insoluble substances, which comprises incorporating in the materials a finely l divided insoluble inorganic compound capable of conversion into the desired insoluble substance by the action of suitable reagents, and applying such reagents to the formed material so as to effect the formation ,of the desired insoluble subi stance in the material.

2. Process for the manufacture of artificial filaments, threads, yarns, films, fabrics andlike materials comprising organic derivatives of cellulose, containing insoluble substances, which comprises incorporating in the materials a finely divided insoluble inorganic compound capable of conversion into the desired insoluble substance by the action of suitable reagents, and applying such reagents tothe formed material so as to effect the formation of the desired insoluble substance in the material.

3. Process for the manufacture of artificial filaments, threads, yarns, films, fabrics and like materials comprising cellulose acetate, containing insoluble substances, which comprises incorporating in the materials a finely divided insoluble inorganic compound capable of conversion into the'desired insoluble substance by the action of suitable reagents, and applying such, reagents to the formed material so as to effect the formation .of the desired insoluble substance in the material.

4. Process for the manufac of artificial fily aments, threads, yarnaggmaf rics and like materials containing inso uble substances, which comprises incorporating in the spinning solution from which they are formed a finely divided insoluble inorganic compound capable of conversion "into tlie desired insoluble substance by the action of suitable reagents, and applying such reagents to the formed material so as to effect the formation of the desired insoluble substance in the material.

5. Process for the manufacture of artificial filaments, threads, yarns, films, fabrics and like materials comprising cellulose acetate, containing insoluble substances, which comprises incorporating in the spinning solution from which they are formed a finely divided insoluble inorganic compound capable of conversion into the desired insoluble substance by the action of suitable reagents, and applying such reagents to theformed material so as to effect the formation of the desired insoluble substance in the material.

6. In the manufacture of artificial filaments, threads, yarns, films, fabrics and. the like comprising cellulose acetate, the step of incorporating .in the spinning solution from which they-are formed a tin compound in finely divided form, and treating the formed products with suitable reagents to convert the said compound into stannic phosphate.

ing in the spinning solution from which they are formed a tin compound in finely divided form,

and treating the formed products with suitable reagents to convert the said compound into stannic phosphate, the quantities being such that the stannic phosphate is present in proportions of at least 10% calculated on the cellulose acetate.

8. Process for the manufacture of filaments,

threads, yarns, films, fabrics and the like comprising organic esters of cellulose, containing insoluble substances, which comprises incorporating in the materials'a finely divided insoluble inorganic compound capable of conversion into the desired insoluble substance by the action of suitable reagents, applying such reagents to the formed material so as to effect the formation of the desired insoluble'substance in the material,

and simultaneously partially saponifying the material.

9. In a process for the manufacture of artificial filaments, threads, yarns, films, fabrics and the like comprising cellulose acetate, containing insoluble substances, the step of incorporating in the spinning solution from which they are formed a finely divided inorganic compound capable of conversion into a substantially white, insoluble substance by the action of suitable reagents, applying such r cuts to the formed material so as to effect the formation of a-substantially white, insoluble substance, and partially saponifying the materials simultaneously with the conversion of the incorporated compound into the white, insoluble substance.

10. In the manufacture of artificial filamen threads, yarns, films, fabrics and the like comprising cellulose acetate, containing insoluble substances, the step of incorporating in the spin- 'ning solution from which they are formed a tin compound in finely divided form, treating they 

